<?php

/*
 * This file is part of the official PHP MCP SDK.
 *
 * A collaboration between Symfony and the PHP Foundation.
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
namespace Matomo\Dependencies\McpServer\Mcp\Server\Handler\Request;

use Matomo\Dependencies\McpServer\Mcp\Capability\Discovery\SchemaValidator;
use Matomo\Dependencies\McpServer\Mcp\Capability\Registry\ReferenceHandlerInterface;
use Matomo\Dependencies\McpServer\Mcp\Capability\RegistryInterface;
use Matomo\Dependencies\McpServer\Mcp\Exception\ToolCallException;
use Matomo\Dependencies\McpServer\Mcp\Exception\ToolNotFoundException;
use Matomo\Dependencies\McpServer\Mcp\Schema\Content\TextContent;
use Matomo\Dependencies\McpServer\Mcp\Schema\JsonRpc\Error;
use Matomo\Dependencies\McpServer\Mcp\Schema\JsonRpc\Request;
use Matomo\Dependencies\McpServer\Mcp\Schema\JsonRpc\Response;
use Matomo\Dependencies\McpServer\Mcp\Schema\Request\CallToolRequest;
use Matomo\Dependencies\McpServer\Mcp\Schema\Result\CallToolResult;
use Matomo\Dependencies\McpServer\Mcp\Server\Session\SessionInterface;
use Psr\Log\LoggerInterface;
use Psr\Log\NullLogger;
/**
 * @implements RequestHandlerInterface<CallToolResult>
 *
 * @author Christopher Hertel <mail@christopher-hertel.de>
 * @author Tobias Nyholm <tobias.nyholm@gmail.com>
 */
final class CallToolHandler implements RequestHandlerInterface
{
    private SchemaValidator $schemaValidator;
    public function __construct(private readonly RegistryInterface $registry, private readonly ReferenceHandlerInterface $referenceHandler, private readonly LoggerInterface $logger = new NullLogger(), ?SchemaValidator $schemaValidator = null)
    {
        $this->schemaValidator = $schemaValidator ?? new SchemaValidator($logger);
    }
    public function supports(Request $request) : bool
    {
        return $request instanceof CallToolRequest;
    }
    /**
     * @return Response<CallToolResult>|Error
     */
    public function handle(Request $request, SessionInterface $session) : Response|Error
    {
        \assert($request instanceof CallToolRequest);
        $toolName = $request->name;
        $arguments = $request->arguments ?? [];
        $this->logger->debug('Executing tool', ['name' => $toolName, 'arguments' => $arguments]);
        try {
            $reference = $this->registry->getTool($toolName);
        } catch (ToolNotFoundException $e) {
            $this->logger->error('Tool not found', ['name' => $toolName]);
            return new Error($request->getId(), Error::METHOD_NOT_FOUND, $e->getMessage());
        }
        $inputSchema = $reference->tool->inputSchema;
        $validationErrors = $this->schemaValidator->validateAgainstJsonSchema($arguments, $inputSchema);
        if (!empty($validationErrors)) {
            $errorMessages = [];
            foreach ($validationErrors as $errorDetail) {
                $pointer = $errorDetail['pointer'] ?? '';
                $message = $errorDetail['message'] ?? 'Unknown validation error';
                $errorMessages[] = ('/' !== $pointer && '' !== $pointer ? "Property '{$pointer}': " : '') . $message;
            }
            $summaryMessage = "Invalid parameters for tool '{$toolName}': " . implode('; ', \array_slice($errorMessages, 0, 3));
            if (\count($errorMessages) > 3) {
                $summaryMessage .= '; ...and more errors.';
            }
            return Error::forInvalidParams($summaryMessage, $request->getId(), ['validation_errors' => $validationErrors]);
        }
        $arguments['_session'] = $session;
        $arguments['_request'] = $request;
        try {
            $result = $this->referenceHandler->handle($reference, $arguments);
            $structuredContent = null;
            if (!$result instanceof CallToolResult) {
                $structuredContent = $reference->extractStructuredContent($result);
                $result = new CallToolResult($reference->formatResult($result), structuredContent: $structuredContent);
            }
            $this->logger->debug('Tool executed successfully', ['name' => $toolName, 'result_type' => \gettype($result), 'structured_content' => $structuredContent]);
            return new Response($request->getId(), $result);
        } catch (ToolCallException $e) {
            $this->logger->error(\sprintf('Error while executing tool "%s": "%s".', $toolName, $e->getMessage()), ['tool' => $toolName, 'arguments' => $arguments]);
            $errorContent = [new TextContent($e->getMessage())];
            return new Response($request->getId(), CallToolResult::error($errorContent));
        } catch (\Throwable $e) {
            $this->logger->error('Unhandled error during tool execution', ['name' => $toolName, 'exception' => $e]);
            return Error::forInternalError('Error while executing tool', $request->getId());
        }
    }
}
